This invention features devices and methods for analyte processing and detection, and use of such methods in the treatment and diagnosis of disease.
Biocompatible magnetic sensors have been designed to detect molecular interactions in biological media. Upon target binding, these sensors cause changes in the spin-spin relaxation times of neighboring water molecules (or any solvent molecule with free hydrogens) of a sample, which can be detected by magnetic resonance techniques. Thus, by using these sensors in a sample, it is possible to detect the presence of an analyte at very low concentration—for example, small molecules, specific DNA, RNA, proteins, carbohydrates, organisms, and pathogens (e.g., viruses).
In general, magnetic sensors are superparamagnetic particles that bind or otherwise link to their intended molecular target to form clusters (aggregates). It is thought that when superparamagnetic particles assemble into clusters and the effective cross sectional area becomes larger, the ability of the clustered superparamagnetic particles to dephase the spins of surrounding water (or other solvent) protons is altered, leading to a change in the measured relaxation rates (e.g., 1/T2). Additionally, cluster formation is designed to be reversible (e.g., by temperature shift, chemical cleavage, pH shift, etc.) so that “forward” or “reverse” assays can be developed for detection of specific analytes. Forward (clustering) and reverse (declustering) types of assays can be used to detect a wide variety of biologically relevant materials.
There is a need in the art for a rapid, commercially realizable, fluidics-based device capable of multiplexed analyte detection suitable for use with magnetic nanosensors.